ORLANDO, FL, USA (UroToday.com) - Radium-223 chloride (Ra-223) is a 1st-in-class alpha-pharmaceutical targeting bone metastases (mets) with high-energy alpha-particles of short range (< 100 μm). ALSYMPCA, a phase III, double-blind, randomized, multinational study, compared Ra-223 plus best standard of care (BSC) vs placebo (pbo) plus BSC in patients (pts) with bone mets in CRPC. The primary endpoint was OS; secondary endpoints included skeletal-related events (SREs).
Eligible pts had progressive, symptomatic CRPC with ≥ 2 bone mets on scintigraphy and no known visceral mets; were receiving BSC; and either previously received docetaxel, were docetaxel ineligible, or refused docetaxel. Pts were randomized 2:1 to receive 6 injections of Ra‑223 (50 kBq/kg IV) q4 wks or matching pbo and stratified by prior docetaxel use, baseline alkaline phosphatase level, and current bisphosphonate use.
922 patients (Ra-223, n = 615; pbo, n = 307) were randomized from 6/2008-2/2011. Based on data from a planned interim analysis (n = 809), unblinded June 2011, Ra-223 significantly improved OS in pts with CRPC with bone mets vs pbo (median OS 14.0 vs 11.2 mo, respectively; two-sided P = 0.00185; HR = 0.695; 95% CI, 0.552-0.875). SREs were lower in the Ra-223 vs pbo group, and time to 1st SRE was significantly delayed (median time to SRE 13.6 mo vs 8.4 mo, respectively; P = .00046; HR = .610; 95% CI, .461-.807).
Ra-223 significantly delayed time to 1st SRE and SRE components, except surgical intervention. These reductions in SREs, particularly SCC, are noteworthy. Ra-223 is an effective therapy with a highly favorable safety profile and may provide a new standard of care for treatment of CRPC pts with bone mets...enlarge and view the full poster.
Presented by N. Vogelzang,1 C. Parker,2 S. Nilsson,3 R. Coleman,4 C.G. O’Bryan-Tear,5 M. Shan,6O. Sartor7 at the 2013 Genitourinary Cancers Symposium - February 14 - 16, 2013 - Rosen Shingle Creek - Orlando, Florida USA
1Comprehensive Cancer Centers of Nevada, Las Vegas, NV, USA; 2The Royal Marsden NHS Foundation Trust, Sutton, UK; 3Karolinska University Hospital, Stockholm, Sweden; 4Weston Park Hospital, Sheffield, UK; 5Algeta ASA, Oslo Norway; 6Bayer HealthCare, Montville, NJ, USA; 7Tulane Cancer Center, New Orleans, LA, USA
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